* SYS functions and GCC 12 fixes
* Add implementation of _gettimeofday and settimeofday, _times
* Remove some GCC warnings about unimplemented SYS functions (e.g. _open) by making weak implementations that return errors.
* Removed _exit from crt0.S since we have a weak version in runtime.c and we don't want two weak impls since the linker can't pick. If the user omits runtime.c then they'll need to provide _exit or get the error
* Add sys/time.h to arch/cc.h for lwIP as it seems under GCC12 this is not getting included
177b0303dd